# Full text of "Text Book Of Mechanical Engineering"

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Appendix II.

I I

I.   ENTROPY OF WATER FROM 32° FAHR.

PER LB. WEIGHT.

t*
r

32
492

50
5io

IOO
560

15°
610

2OO
660

250
710

300
760

35°
810

400
860

*oco

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•295
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We have next to find the additional entropy due to the conver
sion of water into steam. Now at any temperature rx the sensible
heat from 32° is the area SH, and the heat to be supplied in making
this into steam being area Lh, the entropy added = LK -r r — <j>s.
In this manner the second curve c D has been drawn and the
figures in Tables II. and III. obtained:

II. ENTROPY OF STEAM
PER LB. WT.

III. ENTROPY OF STEAM AND
WATER PER LB. WT.

r
_k
T

492
2*219

510
2*116

560
1-865

610
1 655

660
1-476

710
1*322

760
1-188

810
1*070

860
•965

r
0w-f0s

492
2*2f9

510
2*188

560
1*994

610
1-870

660
1*771

710
1*691

760
1*626

810
i '574

860
i*53i

'Hie next problem is  to convert an ordinary j> V indicator
01 into a r\$ diagram, which we shall here solve by the```